In the 2010 version of GMP in the pharmaceutical engineering of the clean level of a Class A, B, C, D four levels, each level has a different process parameters. According to the requirements of the production process clean distinction for 4 levels: a high risk operating area, usually with a laminar flow operating table (cover) to maintain the area of the air environment. Laminar flow system in the work area must be uniform wind, wind speed is 0.36 ~ 0.54m/s (guidance value), the data should prove that the state of laminar flow and must be verified. At a closed operation isolation or glove box, and can be used for one-way flow or lower wind speed; B refers to the aseptic preparation and filling, high risk operation grade a zone in which the background region; grade C and D to sterile drug production process in lower degree of importance of clean operating area. A, B, C level on the static and dynamic requirements, D only to the static requirements. In summer, in the production process on the temperature and humidity has no special requirements, air cleanliness a (b) level, C class pharmaceutical clean room (area) temperature should 20 to 24 DEG C, the relative humidity should be 45% to 60%; the temperature of the air cleanliness class D for the 18 to 26 degrees Celsius relative humidity should be 45% to 65%. Pharmaceutical engineering has sterile drug production, non sterile drug production, raw materials, pharmaceutical production, Chinese medicine preparation, etc..